Exploring genetic diversity of maize (ZEA MAYS l.) accessions in Sri Lanka by employing SSR markers on photosynthetic, canopy architectural and grain yield traits

Abstract

Purpose: The favorable alleles identified in maize landraces are treasurable resources to enhance the genetic base of crop breeding efforts. Therefore, our pioneering research aimed to explore SSR markers related to maize canopy architectural, photosynthetic and yield traits and hence to study the genetic diversity of 19 local maize accessions compared with the high-performing maize cultivar Bhadra, as the standard variety. Research Method: Genomic DNA extraction was done from young leaves of maize seedlings using standard protocols. The SSR markers employed were phi065, phi116, umc1065, umc1066, umc1222, umc1231, umc1545, bnlg155, bnlg249 and bnlg1805. Data analysis was performed using GenAlex and DARwin software. Findings: Four of the used markers (umc1066, bnlg1805, phi116, and phi065) had PIC values higher than that of the overall mean (0.692), showing their potential in this genetic diversity study. These markers are mainly associated with leaf area index, plant height, leaf chlorophyll content and quantum efficiency of photosystem II. The highest genetic diversity measures were observed in SEU2, SEU17, SEU18 and SEU23, compared to Bhadra while the lowest was in SEU3. The level of inbreeding was higher in SEU8. Cluster analysis identified three major genetic groups and the landraces collected from various areas did not exhibit any geographical association. Research Limitations: A large number of SSR markers are needed to explore biomass and grain yield traits. Originality/value: These results will explore the potential uses of Sri Lankan maize accessions to identify the best genetic clusters of germplasm with enhanced plant canopy architecture, photosynthesis and grain yield to be utilized in maize breeding programs.